Iron Mountain has signed an 11-year lease for more than 129,000 square feet at One Federal, Tishman Speyer said Tuesday. Iron Mountain is currently located at 745 Atlantic Ave., which is near Boston’s South Station.

Iron Mountain said it expects to begin its relocation in early 2014. About 600 employees will make the move. (The company has a worldwide headcount of about 17,000.) Iron Mountain will lease about the same amount of space at One Federal as it does at 745 Atlantic, where its operations are currently spread out over eight floors. At One Federal, Iron Mountain will occupy two-and-a-half floors, and the plan is that the new office will make for a more collaborative work environment.

Tishman Speyer described One Federal as a 38-story office tower with about 1.1 million square feet of rentable space. Other tenants include Bingham McCutchen LLP, Aon, Credit Suisse, JP Morgan Chase, Oppenheimer, US Bank, and Leerink Swann.

According to its website, Iron Mountain had $3 billion in 2011 revenues.